To be the biggest, strongest, fastest kid in your school at the age of 12 but then not grow another inch or gain another ounce of athletic ability thru the rest of your young adulthood.

Cheerleader: Who is that 5th grader on the sidelines of the Varsity football game?
Other Cheerleader: Oh girl, that's Turner. He has a bad case of Turnbuckle Syndrome. Poor bastard hasn't grown an inch or gained an ounce of athletic ability since the 5th grade.
Cheerleader: Awww, poor little guy...